"The collapse of the tablet market in 2014 was alarming," said Ranjit Atwal, research director at Gartner.

Atwal said the steep decline is due to the extension in the lifetime of tablets, especially for iOS devices, and a lack of innovation in hardware making punters reluctant to upgrade.

Overall global device sales of PCs, tablets, "ultramobile" PCs and mobile phones for 2015 is estimated to reach 2.5bn; an increase of 3.9 per cent from 2014, according to Gartner. Of those 1.45bn will run on an Android operating system, an increase of 25 per cent from 2014 of all devices sold.

"From 2015, we expect Windows to grow faster than iOS, as the PC market stabilises and the challenge for the next iPhone to find significant growth becomes greater, narrowing the gap between the two operating systems," said Atwal.

At the Las Vegas Consumer Electronics Show mega-bonanza this week, Gartner analysts expect vendors to announce a number of new partnerships.

"We also expect development in cognisant computing to help the vendors' relationships with consumers evolve from passive providers of hardware to in-sync with the user," said Atwal. ®